Improvement in dredging apparatus



UNITED STATES PATENT FFICE JAN JACOB VAN RIETSOHOTEN AND WILLEM HOUWENS,OF ROTTERDAM, NETHERLANDS.

IMPRVEMENT IN DREDGING APPARATUS.

Speeifieation forming part of Letters Patent No. 184,121, dateclNovember 7, 1876; applioatou filed June 26, 1876.

T0 all whom z't may concern Be it known that we, JAN JACOB VANRITSCHOTEN and WILLEM HQUWENS, of Rotterdam, N etherlands, have uventeda new and. Improred Apparatus for Removing Saud Banks, Bars, &o., ofwhieh the followiug is a specifioation In the acoompanying drawing,Figure 1 represents a side elevation of my improved apparatus forremoving saud banks, bars, &o., in rivers; and Fig. 2 is an end view ofthe same.

Similar letters of referenoe inclieate correspondiug parts.

The invention has for its object to provide improved mechanica]applianees for removing sand. banks and bars, aud deepeningwateroourses, rivers, canals, &o.; and L consists of an mprwement; inpropellers driven by suit able motive power, and working partially inthe material or sandbank to be removed, so oausing whirlpools, and.bringiug t;l1e mud or sand. into a state of suspension in tlie water,

and employing the eurrent to oarry awa y tl1e material thus brought intosuspension into deep water. '1 he propellers are oarried at; the

ends of beams, whiol1, at tl1eir opposite euds, are hun g to a lateralframe of a barge or vessel. 'll1e euds of the beams carry back of thepropellers rollers to run upon the mud or sanrl and prevent: tl1epropellers aud beams 'rom entering too deeply iuto it.

'll1e propellers anrl beams may be lifted by ohains or otherwisis, po betl1eu used simply 'or propelling the vessel, whieh may tl1us be used inbroken water, where the use of an ordiuary dredgiug-maehiue isimpossible.

In the drawiug, A A are the beams, of snit able ooustruotiou andlengtl1, tlrat are hang al;

the upper euds to a shaft, A that is supported in bearings of a lateralframe, A of a suitable barge or vessel, aml lrlveu by a steam-engine onboard of the same. The

drivingshaft A revolves, by beveled gearwheels, the shafts B, that; turnin bearngs of IJhe beams, aud are provided al: their lower ends with apropeller or propellers, B. Eaeh propeller or stirrer B consists of afour-bladed. sorew of unusual streugtlx, wibh two blades set in advanoeof, and being somewhat longer than, the other two. Tl1e propellers arelowered to the bottom of the rver, oanal, or other water-courses, andthen remlved to work on the sand-bank or materlal to be removed, so tostir up the same and brng it; uto a suffioient; state of suspension inthe water to admt; of its beng oarred away by tlxe ourrent. A roller orrollers, O, are arranged back of the propellers, turning in suitablebearings of the beams A, to prevent the propellers from entering toodeeply into the mud so as to break or g'et stook.

Tl1e propellers and beams are lifted by means of cl1aius D and orane Dinto position alongside of the vessels, when the work of removing thesand is to be interrupted, tl1e propellers servng t;l1en to move tlxevessel.

Tl1e lifting-ehain is taken in by a steamwineh, tl1e propellers andbeams beiug in tllis marmer readily raised for movlug aud lowered forwork. Guard pieees or bands at tl1e sirles of the vessel serve to guidetl1e beams as they are raised or lowered.

Having thus desoribed our invention, what we claim as uew, aud desire tosecure by Letters Patenn, is-

JAN JACOB VAN RIETSCHOTEN.

WILLEM HOUWENS. Witnesses: A. SCHOUPT,

A. F. G. HEUFTMAN.

